PMID: 22753105
Webster MP, Jukes R, Zamfir VS, Kay CW, Bagneris C, Barrett T
Crystal structure of the UvrB dimer: insights into the nature and functioning of the UvrAB damage engagement and UvrB-DNA complexes.
Nucleic Acids Res. 2012 Sep 1;40(17):8743-8758. Epub 2012 Jun 30.
UvrB has a central role in the highly conserved UvrABC pathway functioning not only as a damage recognition element but also as an essential component of the lesion tracking machinery. While it has been recently confirmed that the tracking assembly comprises a UvrA(2)B(2) heterotetramer, the configurations of the damage engagement and UvrB-DNA handover complexes remain obscure. Here, we present the first crystal structure of a UvrB dimer whose biological significance has been verified using both chemical cross-linking and electron paramagnetic resonance spectroscopy. We demonstrate that this dimeric species stably associates with UvrA and forms a UvrA(2)B(2)-DNA complex. Our studies also illustrate how signals are transduced between the ATP and DNA binding sites to generate the helicase activity pivotal to handover and formation of the UvrB(2)-DNA complex, providing key insights into the configurations of these important repair intermediates.